Bigger Trim Tabs? (30-40 Foot MY)

[sweetchief]

Does anyone have any information on the effects of larger trim tabs for a 35-40 Cabin Cruiser?<br /><br />I currently have 18 X 12 trim tabs on 352 Silverton. Bennett says I would benift from 42 X 9's or 48 X 9's. <br /><br />Will putting larger trim tabs on my 38 foot boat help me with gaining any cruise speed?

 

[QC]

Re: Bigger Trim Tabs? (30-40 Foot MY)

Welcome to iboats SweetChief!! Nice ride. This is a larger boat than most guys here have experience with (me too darn it), but I have a couple of questions that might help get to the answer.<br /><br />Does the boat plane efficiently now? If she is squatting really low and digging a big hole as is, then bigger tabs may help. If she is already getting up and planing and you are able to bring the tabs up and keep her on plane, then I doubt larger tabs will have a noticeable effect on top speed or cruise speed.<br /><br />What speed are you cruising at now? Max speed?<br /><br />BTW, my experience with Bennett as a company is that they are very honest and very good at what they do

 

[sweetchief]

Re: Bigger Trim Tabs? (30-40 Foot MY)

At cruise speed (13-15 knots) I have to go with tabs full down. If I pull the tabs up I only cruise 12-13 knots. Riding at cruise it feels like she is squating. WOT I can ride a nice plane with trim tabs full down and I get 24 knots.

 

[tgissel]

Re: Bigger Trim Tabs? (30-40 Foot MY)

Sweetchief,<br />I recently changed mine over from 18" x 12" to 24" x ? (16" or 18"). It made a difference on my 30' Marinette keeping it on plane at less RPM and much quicker on adjusting for correcting a list. I also use Bennetts auto-trim, alot of people bad mouth it but I enjoy having it and you can turn it off and manually operate the tabs yourself, it automatically corrects for listing.<br /><br />I would say you could use a bigger tab, if you have them full down at WOT they are probably holding back alot of your potential.<br /><br />Good luck

 

[QC]

Re: Bigger Trim Tabs? (30-40 Foot MY)

I agree with tgissel. I am curious what happens when you bring the tabs up a little at WOT?<br /><br />BTW, love your boat tgissel. Saw her on Show Yer Boat II. What a sweetheart!!